1. Field of the Invention
The present invention relates to a content sales site and a program applied to the content sales site.
2. Description of the Related Art
There exist web sites which online-market to users various data including MIDI data, electronic musical score data, incoming-call melody data, and karaoke data (hereafter referred to as “content”). When users purchase content items from those web sites, users find it inconvenient to manage purchased content items as the number of them increases. Such inconvenience could cause users to repurchase unnecessary content items which they have already purchased. It could also cause them to buy content items which have been preset in their terminal device such as electronic musical instrument or mobile communication terminal device (hereafter referred to as “electronic musical apparatus”). As a result, such situations make users pay for unnecessary content items.
In Japanese Non-examined Patent Publication No. 07-129604 (Hiuka Sangyo KK, System Gijutsu Kenkyusho KK), there is disclosed a system entitled “REMOTE LIBRARY SYSTEM FOR PURCHASED ELECTRONIC BOOK DATA”. According to this system, once a user purchases an electronic book data object from an electronic book data supply center, the center records the data object in a catalog listing all data objects that the user has purchased. When the user requests the catalog, it is sent from the center to the user's electronic book. From among the data objects listed in the catalog, the user selects one of purchased electronic book data objects to be transferred from the center to the user's electronic book. By following above procedure, the user can record a purchased electronic book data object on his/her electronic book any number of times.
That is, the user can use the electronic book center as storage space which stores purchased electronic book data objects and retrieve a desired object at any time. This usage serves to reduce storage space of the electronic book and to prevent one object from being stored in plural spaces. On purchasing a new data object, however, there arises an inconvenience that the user cannot make a judgement whether the user has already owned it until the user requests the purchased data catalog in order to confirm that it is not in the catalog.
Another related art is a system for retrieving content items, which is entitled “INFORMATION PROCESSOR, INFORMATION PROCESSING METHOD AND PROVIDING MEANS” (Japanese Non-examined Patent Application No. 2000-293586: SONY CORP). According to this system, information on content items which a user purchased from content providers is retained by the user's device (a receiver in the user's network). If the user re-purchases a content item which the user has already owned, the user is charged at a reduced price which is set by the user's device.
This system can serve to reduce prices of content items which are repurchased. In this system, however, prices have to be set by users' devices which manage information. Users' devices also have to check whether frauds such as information tampering are perpetrated or not. As a result, this system causes inconvenience that these loads placed on users' devices complicate the device configuration.